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.Dd March 15, 2012
.Dt KILLPG 2
.Os
.Sh NAME
.Nm killpg
.Nd send signal to a process group
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In sys/types.h
.In signal.h
.Ft int
.Fn killpg "pid_t pgrp" "int sig"
.Sh DESCRIPTION
The
.Fn killpg
function
sends the signal
.Fa sig
to the process group
.Fa pgrp .
See
.Xr sigaction 2
for a list of signals.
If
.Fa pgrp
is 0,
.Fn killpg
sends the signal to the sending process's process group.
.Pp
The sending process must be able to
.Fn kill
at least one process in the receiving process group.
.Sh RETURN VALUES
.Rv -std killpg
.Sh ERRORS
The
.Fn killpg
function
will fail and no signal will be sent if:
.Bl -tag -width Er
.It Bq Er EINVAL
The
.Fa sig
argument
is not a valid signal number.
.It Bq Er ESRCH
No process can be found in the process group specified by
.Fa pgrp .
.It Bq Er EPERM
.Fn kill
returns EPERM for all processes in the process group.
.El
.Sh SEE ALSO
.Xr getpgrp 2 ,
.Xr kill 2 ,
.Xr sigaction 2
.Sh HISTORY
The
.Fn killpg
function appeared in
.Bx 4.0 .
